New Hair Shader

V-Ray V-Ray for 3ds Max Issues
1

Hi,

im playing with the new hair shader in vray… but i get strange results…

im using a standard linear workflow… a sunlight, no environment sky and two area lights.. gi brute force and light cache with retrace theshold turned on… im using mrprim and the vray shader in the hair modifier…

but i get allways a dark area where normally should be the brightest place…

any ideas..?

hair1.jpg
hair1.jpg820×455 136 KB

2

What makes you think this should be the brightest place?

Best regards,
Vlado

3

This is a comparison between the new hair material (left side) and a normal vray mat (right side).

The weird thing is the complete lack of highlights in the hotspot area of the sunlight with the hair material.
Maybe this is how hair should look like - I don’t know:)

highlights.jpg
highlights.jpg527×467 105 KB

4

The difference comes from fact that in new hair material you’ve set stronger specular input than diffuse.
Specular light on hair tend to make such halo like effect because the for them light are stronger for strands which are perpendicular to light.
You can always try to blend those two materials.

5

next strange thing is that the bias in the hairInfoTex isnt moving the midpoint.
its working more like a falloff from the middle.
if you lower the value the falloff is getting harder.
if you go over .5 it not working at all.

looks like there is no way to get a transparency only on the tip of the hair strand…

bias1.jpg
bias1.jpg719×923 183 KB

6

Hm, there seems to be a problem with that indeed. I’m looking into it.

Best regards,
Vlado